Patent GB-709579-A (GB)
Title: Improvements in double windows
IPC: E06B3/28
Filed: 1951-11-23
Abstract: 709,579. Double glazing. FEGAN, T. G. Oct. 31, 1952 [Nov. 23, 1951], No. 27500/51. Class 20 (3) A mounting for a supplementary glazing sheet 3, Fig. 4, to convert a single glazed window into a double glazed one, comprises strips 4 of grooved resilient material such as rubber, latex foam or polyvinyl chloride, fitted along the edges of sheet 3 with lengthwise ribs 7, 8 on both sides of the strips and clips 5 secured at intervals to the window frame 1 and movable to press the grooved strips 4 into sealing engagement with the frame 1. The frame 1 may be the sash or casement as shown or it may be the surrounding frame in which the glazed sashes are fitted. Each clip 5, Fig. 5, consists of a back plate 12, apertured at 13 to receive the fixing screw 11, finger-grips 14, stiffening ribs 15, and part-spherical projection 16, each clip being mounted on a distance piece 10 which is slightly smaller than the overall thickness of strip 4, with projection 16 engaging the strip 4 between ribs 7, 8. To release the sheet 3 and its surrounding strips 4, the clips 5 are pivoted about their screws 11 whereupon the sheet 3 may be removed, reversed and replaced. In a modification the clip is formed without ribs 15 and the finger grip has a portion extending parallel to the back plate. Instead of one large supplementary sheet 3, two sheets may be provided with the strips 4 of adjacent sheets abutting to form a seal. In a modified form of strip 25, Fig. 12, a single rib 26 at each side contains a lengthwise tule 27 forming an air cushion. In a further form a rib along each side contains an internal channel providing an air cushion. In another embodiment two supplementary glazing sheets are provided to form a triple glazed window, the lower rib of the outer sealing strip being positioned between the ribs of the inner sealing strip and the part spherical projection on the clip acting between the two outer ribs of the outer strip. In a further form the second supplementary glazing sheet is replaced by a mosquito netting whose edges are folded or wired to stiffen them and to add thickness for fitting the grooves of the strips. As shown in Fig. 16, the supplementary sheet 49 provided with sealing strips 50 and with its bottom edge resting on distance pieces 51 of clips 52 has its top edge held clear of frame 46 by supporting each side edge by an outer bar 53 of a clip secured on a distance piece 54, an inner bar 55 of each clip enabling the sheet 49 to be held in sealing contact with the frame when required. In a modification the sheet 49 may be replaced by two sheets, the upper one being removed when ventilation is required or alternatively raised a little off the lower sheet by providing a distance piece at each end. If radial ventilators, flap type ventilators or small fans are fitted to the supplementary glazing sheet a conduit is fitted between it and the original glass sheet. The bottom of the space between the sheets or the grooves of the strips may be provided with moisture absorbing material. According to the Provisional Specification a supplementary pane may be mounted over the lower part only of a window, a filler strip being inserted between its top resilient strip and the top of the lower sash when the supplementary pane is mounted on the window frame.